{"id":11243,"date":"2026-07-26T02:31:40","date_gmt":"2026-07-26T02:31:40","guid":{"rendered":"https:\/\/ic-vendor.com\/043703-5wra\/"},"modified":"2026-07-26T02:31:40","modified_gmt":"2026-07-26T02:31:40","slug":"043703-5wra","status":"publish","type":"post","link":"https:\/\/ic-vendor.com\/zh\/043703-5wra\/","title":{"rendered":"043703.5WRA"},"content":{"rendered":"

\u4ea7\u54c1\u6982\u89c8<\/h2>\n

The Littelfuse 043703.5WRA is a 3.5A time-lag (T) surface-mount fuse in a 1206 (3225 metric) chip package. 125VAC\/100VDC rated voltage for overcurrent protection in power supply and battery circuits.<\/p>\n

\u4e3b\u8981\u89c4\u683c<\/h2>\n\n\n\n\n\n\n\n\n\n\n
Rated Current<\/td>\n3.5 A<\/td>\n<\/tr>\n
Rated Voltage<\/td>\n125 VAC \/ 100 VDC<\/td>\n<\/tr>\n
Fusing Characteristic<\/td>\nTime-Lag (T)<\/td>\n<\/tr>\n
I2t (Melting)<\/td>\n~12 A2s<\/td>\n<\/tr>\n
Breaking Capacity<\/td>\n100A @ 125VAC \/ 50A @ 100VDC<\/td>\n<\/tr>\n
Cold Resistance<\/td>\n~0.033 Ohm<\/td>\n<\/tr>\n
Pre-Arcing Time @ 4xIn<\/td>\n0.05s to 5s<\/td>\n<\/tr>\n
\u5de5\u4f5c\u6e29\u5ea6<\/td>\n-55 to +125C<\/td>\n<\/tr>\n
\u5305\u88c5<\/td>\n1206 (3225 Metric, 3.10×1.55mm)<\/td>\n<\/tr>\n<\/table>\n

\u7279\u70b9<\/h2>\n
    \n
  • Time-lag characteristic for inrush tolerance<\/li>\n
  • 1206 compact chip package<\/li>\n
  • 100A high breaking capacity<\/li>\n
  • UL and cUL listed<\/li>\n
  • RoHS compliant<\/li>\n<\/ul>\n

    \u5e94\u7528<\/h2>\n
      \n
    • DC-DC converter input overcurrent protection<\/li>\n
    • Battery pack short-circuit protection<\/li>\n
    • USB power delivery port protection<\/li>\n
    • Industrial supply rail fuse<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The Littelfuse 043703.5WRA is a 3.5A time-lag (T) surface-mount fuse in a 1206 (3225 metric) chip package. 125VAC\/100VDC rated voltage for overcurrent protection in power supply and battery circuits. Key Specifications Rated Current 3.5 A Rated Voltage 125 VAC \/ 100 VDC Fusing Characteristic Time-Lag (T) I2t (Melting) ~12 A2s Breaking Capacity 100A […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[13,56],"tags":[2517],"chip_brand":[200],"class_list":["post-11243","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-mosfets","tag-043703-5wra","chip_brand-littelfuse"],"acf":{"brief_explanation":"3.5A time-lag SMD fuse, 125VAC\/100VDC, 1206, 100A breaking, -55 to 125C","date_code":"","package_case":"1206 (3225 Metric, 3.10x1.55x0.60mm)","in_stock":10753,"datasheet":"https:\/\/www.littelfuse.com\/products\/fuses\/surface-mount-fuses\/437-series.aspx","price":"\/tmp\/tmpg52h2ah6.sh.15 @ 1ku","product_introduction":"The 043703.5WRA from Littelfuse is a 3.5A time-lag (T) surface-mount chip fuse in a 1206 (3225 metric) package from the 437 series. Rated at 125VAC\/100VDC with 100A breaking capacity, it provides reliable overcurrent protection with inrush current tolerance. The time-lag characteristic allows temporary overload from capacitor charging and motor start-up without nuisance blowing. UL and cUL listed for safety compliance.","working_principle":"The 043703.5WRA uses a thin metallic fuse element deposited on a ceramic substrate inside a molded epoxy package. During normal operation below 3.5A, the element carries current with minimal voltage drop. When overcurrent exceeds the melting I2t threshold (~12A2s), resistive heating melts the fuse element, permanently opening the circuit. The time-lag characteristic is achieved by a wider element cross-section that absorbs transient energy (inrush) but melts under sustained overcurrent. The ceramic substrate provides arc-quenching capability during high breaking capacity events.","pin_description":"
      Pin<\/th>Name<\/th>Type<\/th>Description<\/th><\/tr>
      1<\/td>Term 1<\/td>Passive<\/td>Fuse terminal 1 (non-polar)<\/td><\/tr>
      2<\/td>Term 2<\/td>Passive<\/td>Fuse terminal 2 (non-polar)<\/td><\/tr><\/table>","application_scenarios":"
      • DC-DC converter 12V input overcurrent protection<\/li>
      • Li-ion battery pack short-circuit fuse<\/li>
      • USB PD 20V\/3A port protection<\/li>
      • Industrial 24V supply rail fuse<\/li><\/ul>","alternative_models":"
        Model<\/th>Manufacturer<\/th>Key Difference<\/th><\/tr>
        0437003.5WRNL<\/td>Littelfuse<\/td>Same without leads (N suffix)<\/td><\/tr>
        0603F3.5A-TR1<\/td>Bel Fuse<\/td>3.5A 0603 fast-acting alternative<\/td><\/tr><\/table>"},"_links":{"self":[{"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/posts\/11243","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/comments?post=11243"}],"version-history":[{"count":0,"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/posts\/11243\/revisions"}],"wp:attachment":[{"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/media?parent=11243"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/categories?post=11243"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/tags?post=11243"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/chip_brand?post=11243"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}